Telegraphy



Jul 25, 1939. H MUTH 2,167,461

TELEGRAPH! Filed June 2, 1937 INVENTOR HERBERT MUTH 'ri'oRNEY PatentedJuly 25,1939 2,167,461

TELEGRAPH! Herbert Muth, Berlin, Germany, assignor to Telefunken Gesellschaft fiir Drahtlose Telegraphie m. b. H., Berlin, Germany, a corporation of Germany hpplicafiqn June 2, 1937, Serial No. 145,959 In Germany February 1, 1936 2 Claims. (91. 178-66) 7 with the result that the oscillatory circuit L:

This invention relates to a transmitter arrangement for the production and transmission of brief impulses.

This invention is concerned with the producpul'se rhythm. I f

An exemplified embodiment of the invention shall be described in what follows by reference to the accompanying drawing wherein Figures 1 and 2 show two embodiments of my means for producing short impulses. 1 i

Supp e the self-oscillatory tube i comprising the oscillatory circuit Ll Cl produces'wave energy of a frequency fr, while tube 2 with oscillation circuit Lo C: produces a frequency 1:. The ensuing two'waves, are modulated or beat in tube .3

C: wave energy of'a frequency equal to either the sum or the difference .of f1 andjz'is filtered out and fed directly into the antennal! or by way of an additional stage I II. as in Figure 2, to the antenna i2.

If, then, by way of the choke 0011 D the grid of v the .tube 3 is blocked for the alternating potenll of the generators-i and 2, the'mixing process in 3 will be discontinued and as a consequence of insufllcient neutralization of. tube 3, which maybe neutralized as shown in dotted lines, the aerial will radiate only the frequency h or ire- 5 tion of brief radio frequency impulses, especially quency I: to which, however, the receiver appathe kind used for measuring distances and for ratus will not respond. direction finding work. The circuit organization here disclosed makes The keying of radio frequency transmitters it possible in the simplest possible way to disat the rate and rhythm of the desired impulses pense with the keying of a self-oscillatory tube may be effected either in the control or-master regardless of difliculties of neutralization in mas- 10 stage itself or in one of the following amplifier ter operated stages.

' Stages e keyihg 0f lf-osc ato y tub It will be understood that the mixer tube may w v r, nv l h dr w a k h the l ngth. be followed by additional amplifier stages demplitude and the form of the imp lses re a signed for the sum or thel'diiference of the two function to a marked degree of the p va g constituent frequencies f1 and'fz as shown in Fig- 15 regeneration conditions of ,the tube and that ure 2, and these, if necessary, for complete suptherefore the feedback can not lie-altered withpression of antenna, radiation during the spacing out causing. an incidental efiect upon the said periods could be keyed as shown simultaneously characteristics of the impulses. In the case of th th mixer tube.

k yi m s x t stages In w r For the urpose of stabilization of the trans- 20 t by the blocking and oc of the mitted radio. frequency energy it will also be a p fier tubes b e u s are p u one readily possible to stabilize the two tubes i and 2 diificulty arises in the tte pt o neu r lize t by ways and means well known in the prior art,

' amplifier stages. As a result of neutralizing desay, by the aid of monitor quartz crystals.

fects of the keyed stages, as will be seen, radio, If th ixer tube is of the twin-grid type, then 85 frequency oscillations are liable, during the keymerely one grid need to be subjected to keying ing intervals (spacing periods), to flow from the ti master or-pilot stage into the aerial, with the 1 5 1 v result that waves would be sent out also during 1. In means for producing high frequency impa i Per pulses ofshort and'substantially uniform dura- Now, according to this invention 'the shorttion, a, plurality of sources of high frequency 0 ns residing, in the two'keying methods herewave energy, a utilization circuit, an electron inbefore mentioned is obviated 'bythat an interdischarge tube amplifier having input and output mediate f q n Obtained y h mixing tW electrodes, means coupling said input electrodes 85 different frequencies is transmitted at the 1111- to said sources :of high frequency. wave energy 85 whereby said high frequency wave energies are impressed thereon to be beat against each other therein, circuit means, tuned to respond only to a'frequency resulting from said beatingaction,

"coupled to said output electrodes and to said 40 utilization circuit whereby waves of said fre- I quency resulting from said beating action. only reach said utilization circuit, and means includ-' .in'g a key and a source of potential connected with the electrodes 0! said tube to key said tube on andoif whereby high frequency wave impulses of short and substantially constant duration are transferred by said output circuit to said utilize tion circuit.

2. In means for producing high frequency impulses of short and substantially uniform duration. a pair'of sources of high frequency wave energy, a utilization circuit, a plurality of electron discharge tube amplifiers each having input and output electrodes, means coupling the input 5 against each other in said one tube, circuit means, tuned to respond only to a frequency resulting from said beating action, coupling the output electrodes of said one tube to the input electrodes of the other tube, means coupling the output electrodes of said other tube to said utilization circuit, whereby waves of said frequency resulting from said beating action only are transferred by said tubes to said utilization circuit, and means for keying said tub'es on and off whereby high frequency wave impulses of short and substantially constant duration are impressed on said utilization circuit.

HERBERT MUTH. 

